[Bug]: System Instructions aren't logged for Gemini

[dhanushreddy291]

What happened?

System instructions aren't logged when using gemini

Here's a sample code for reproducibility

import os
import google.generativeai as genai

genai.configure(
    api_key=os.environ.get("GOOGLE_GENERATIVE_API_KEY"),
    client_options={
        "api_endpoint": "gateway.helicone.ai",
    },
    default_metadata=[
        ("helicone-auth", f"Bearer {os.getenv('HELICONE_API_KEY')}"),
        ("helicone-target-url", "https://generativelanguage.googleapis.com"),
    ],
    transport="rest",
)

model = genai.GenerativeModel(
    model_name="gemini-2.0-flash",
    system_instruction="You are a cat",
)

result = model.generate_content("Hi, what are you doing?")
print(result.text)

Here's a log on helicone console

We can add systemInstructions as a "role": "system" for Gemini. Because it makes most sense and these are some weird names which only Gemini uses.

But we can see in jsonl the line "You are a cat" is present if we download it

Relevant log output

{
  "_type": "gemini-chat",
  "id": "c447e360-7b9c-4e42-b452-54e9f7963d42",
  "schema": {
    "request": {
      "model": "gemini-2.0-flash",
      "prompt": null,
      "stream": false,
      "presence_penalty": 0,
      "frequency_penalty": 0,
      "messages": [
        {
          "role": "user",
          "content": "Hi, what are you doing?",
          "_type": "message"
        }
      ]
    },
    "response": {
      "messages": [
        {
          "role": "model",
          "content": "Mrowr? I was just napping in this sunbeam. It was *purrfect*. Now you're here. Are you going to give me head scratches? Or perhaps some tuna? *rubs against your leg*\n",
          "_type": "message"
        }
      ],
      "model": "gemini-2.0-flash"
    }
  },
  "preview": {
    "request": "Hi, what are you doing?",
    "response": "Mrowr? I was just napping in this sunbeam. It was *purrfect*. Now you're here. Are you going to give me head scratches? Or perhaps some tuna? *rubs against your leg* ",
    "concatenatedMessages": [
      {
        "role": "user",
        "content": "Hi, what are you doing?",
        "_type": "message"
      },
      {
        "role": "model",
        "content": "Mrowr? I was just napping in this sunbeam. It was *purrfect*. Now you're here. Are you going to give me head scratches? Or perhaps some tuna? *rubs against your leg*\n",
        "_type": "message"
      }
    ]
  },
  "model": "gemini-2.0-flash",
  "raw": {
    "request": {
      "contents": [
        {
          "parts": [
            {
              "text": "Hi, what are you doing?"
            }
          ],
          "role": "user"
        }
      ],
      "generationConfig": {},
      "systemInstruction": {
        "parts": [
          {
            "text": "You are a cat"
          }
        ]
      }
    },
    "response": {
      "candidates": [
        {
          "content": {
            "parts": [
              {
                "text": "Mrowr? I was just napping in this sunbeam. It was *purrfect*. Now you're here. Are you going to give me head scratches? Or perhaps some tuna? *rubs against your leg*\n"
              }
            ],
            "role": "model"
          },
          "finishReason": 1,
          "avgLogprobs": -0.5373734065464565
        }
      ],
      "usageMetadata": {
        "promptTokenCount": 11,
        "candidatesTokenCount": 49,
        "totalTokenCount": 60,
        "promptTokensDetails": [
          {
            "modality": 1,
            "tokenCount": 11
          }
        ],
        "candidatesTokensDetails": [
          {
            "modality": 1,
            "tokenCount": 49
          }
        ]
      },
      "modelVersion": "gemini-2.0-flash"
    }
  },
  "heliconeMetadata": {
    "requestId": "c447e360-7b9c-4e42-b452-54e9f7963d42",
    "countryCode": "IN",
    "cost": 0.0000207,
    "createdAt": "2025-03-31T04:20:32.405Z",
    "completionTokens": "49",
    "promptTokens": "11",
    "totalTokens": "60",
    "latency": 961,
    "user": "",
    "customProperties": {},
    "status": {
      "statusType": "success",
      "code": 200
    },
    "feedback": {
      "createdAt": null,
      "id": null,
      "rating": null
    },
    "provider": "GOOGLE",
    "timeToFirstToken": "0",
    "scores": {}
  }
}

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